[Bf-committers] Inverse Shrinkwrap? (only "keep above surface")

[Tobias Oelgarte]

Shrinkwrap is designed to force vertices onto the surface of another 
object. In Nearest Surfacepoint mode it moves vertices either to the 
surface or optionally let it also move outward until they are on the 
surface. So you can work with essential two options. But wouldn't it 
make more sense to include also the possibility that vertices can also 
only be moved up onto the surface and and not moved toward it?

It would allow you to throw a ball against a window, making the vertices 
stop that would pass trough it. There are many possible usages i could 
think of: Bubbles in a glass. Shoes that not sink slightly into the 
ground. Body parts that "collide" with each other, and many more.

Since the algorithm seams to handle this case already -- knowing if a 
vertex is inside or outside the target, for "Keep above surface"  -- it 
should be just an additional option. Am i right?

Cases (now):
* Shrink to Surface
* Shrink to Surface and move outward for "keep above"

Cases (desired):
* Shrink to Surface
* Only "keep above"
* Shrink to Surface and move outward for "keep above"

Hope this is a little inspiration. It would make shrinkwrap much more 
awesome.

Greetings from
Tobias Oelgarte